MCQ
If $y = f(x) = ax^2 + 2bx + c = 0$ has Imaginary roots and $4a + 4b + c < 0$ then :-
- A$c>0$
- ✓$c<0$
- C$c = 0$
- Ddata insufficient
✓
Answer
Correct option: B.
$c<0$
b
Let $f(x)=a x^{2}+b x+c$ has Imaginary Roots
Let $f(x)=a x^{2}+b x+c$ has Imaginary Roots
$f(2)=4 a+4 b+c<0 \Rightarrow f(2)<0$
so $f(0) =c<0$
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